Renal cell carcinoma with renocolic fistula presenting as an emphysematous pyelonephritis in a non-functioning kidney: case report

Background The uniqueness of this case is in its rarity and divergent presentation. Case presentation Here, we report a case of 56-year-old male patient with pain in the left flank for 1 year. On evaluation, patient was diagnosed with multiple left renal calculi and emphysematous pyelonephritis with non-functioning kidney. Intraoperatively, dense perinephric adhesions, necrotic kidney and renocolic fistula were encountered. The patient underwent left nephrectomy with resection anastomosis of descending colon segment with loop ileostomy. Histopathological examination showed a poorly differentiated high-grade clear cell carcinoma with squamous metaplasia. Conclusion Renal cell carcinoma can present in unusual ways. Sometimes, it can mimic emphysematous pyelonephritis because of fistulous communication with gut. It is rare but challenging for urologists to diagnose and manage such cases.